week 13

What is Science?

• Science is the human effort to find order, predictability, consistency, and repeatability in nature.

• By recognizing patterns in how things behave, we can make predictions.

2. The First Step: Observing Patterns

• Scientists first ask: “What happens over and over in nature?”

• They collect data and look for patterns in that data.

• When consistent patterns are found, scientists describe them using scientific laws.

3. Scientific Laws

• A scientific law describes what always happens under certain conditions (e.g., Law of Conservation of Matter: matter is neither created nor destroyed during chemical reactions).

• Laws do not explain why something happens—they just describe what happens.

• Scientific laws are unbreakable and not like human or societal laws, which are voluntary and can be disobeyed.

4. Moving to the Why: Hypotheses

• Scientists then ask the more satisfying question: “Why does this happen?”

• To answer that, they propose a scientific hypothesis—a tentative explanation.

• He uses the example of gravity vs. a silly hypothesis about an invisible rubber band pulling the eraser down.

5. Testing Hypotheses

• Hypotheses are tested with experiments.

• Each experiment results in either a pass or fail:
  

  • A fail means the hypothesis is wrong—discard it.

  • A pass increases confidence in the hypothesis, but does not prove it.

• The more a hypothesis passes tests from different scientists over time, the more confidence builds.

6. Scientific Theory

• When a hypothesis has passed many rigorous tests across time, people, and places, it can become a scientific theory.

• A theory is a well-substantiated explanation that answers the why question and represents the highest level of understanding in science.

Final Message

• Science is a process of discovery.

• It moves from data → laws → hypotheses → experiments → theories.

• It values evidence, repeatability, and testing, and always remains open to revision.

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What Is a Scientific Theory?

• A scientific theory is not just a guess or idea — it’s a well-tested and widely accepted explanation for a phenomenon.

• You can never prove a theory to be absolutely correct. Instead, you gain confidence in it through repeated testing.

• Scientific theories are based on overwhelming evidence, but they are always open to revision if new, better data comes along.

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You Can’t Prove a Theory

• Proof implies something is guaranteed to be true forever — which science doesn’t claim.

• You can disprove a hypothesis, but you can’t prove it permanently correct.

• With each successful test, your confidence grows, but proof is never absolute.

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Consensus vs. Frontier Science

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Consensus Science

• Well-established and widely agreed upon by scientists.

• Tested extensively over time.

• Reliable and stable — e.g., gravity, conservation of matter (with qualifications).

• Not newsworthy because it’s already known and accepted.

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Frontier Science

• New, cutting-edge ideas and discoveries.

• Still being tested, not yet widely accepted.

• Often newsworthy, but less reliable until further validation.

• The public often sees only frontier science, leading to a false impression that science is unstable or frequently wrong.

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Public Perception Problem

• Media focuses on frontier science (new ideas), not consensus science (established facts).

• This can make science seem unreliable, when in fact, most of science is very solid.

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Real-World Example: Medicine

• In medicine, consensus science is critical before applying treatments — especially when lives are at stake.

• But the need for new solutions (like during the COVID-19 pandemic) pushes frontier science into the spotlight.

• Agencies like the FDA regulate when new discoveries are ready for public use.

Key Concepts from the Video

1. The FDA’s Role

• The FDA does not conduct testing itself. It reviews and evaluates data submitted by drug developers.

• It determines whether enough testing has been done and either approves or denies the drug for market release.

• It often faces pressure from:
  

  • Pharmaceutical companies wanting to sell drugs quickly.

  • Patients in urgent need of new treatments.

2. The Testing Process

• Begins with tissue samples, then moves to animal testing (mice, rats).

• Eventually progresses to primates (e.g., chimpanzees) for closer human similarities.

• Finally, clinical trials on human volunteers, who give informed consent.

• Pregnant women are excluded due to:
  

  • Two lives being at risk.

  • The fetus cannot consent.

  • Developing fetuses are more vulnerable to chemical damage.

3. The Thalidomide Tragedy

• Thalidomide was developed as an anti-nausea drug, particularly effective for morning sickness.

• Approved in Europe, but delayed in the U.S. due to FDA backlog — a delay that saved lives.

• Thousands of babies were born with severe limb deformities after their mothers took the drug in early pregnancy.

• The problem: Thalidomide inhibits limb development during early fetal cell differentiation — something never tested for.

• Once the link was discovered, it was pulled from markets, but the damage was done.

4. Lessons Learned

• The tragedy highlighted the importance of:
  

  • Rigorous testing across varied conditions (especially pregnancy).

  • The precautionary principle in drug approval.

  • Reading drug information sheets, especially for side effects, interactions, and warnings (e.g., use in pregnancy often marked as “unknown”).

5. Thalidomide Today

• It’s back on the market, used under strict conditions for diseases like leprosy and multiple myeloma.

• Still not used in pregnancy due to its known effects on fetal development.

What Is Technology?

• Many people confuse science and technology, but they’re not the same.

• Science is the study and understanding of how nature works.

• Technology is the use of products and processes designed to improve our lives.

• It’s not just electronics—technology includes any invention that makes tasks easier, faster, or more efficient.

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Science and Technology Relationship

• They are different but deeply connected.

• Science often leads to new technology (e.g., discoveries turn into inventions).

• Technology can lead to scientific discoveries (e.g., new tools allow better experiments).

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Example: The Laser

• Scientists hypothesized a new behavior of light.

• The idea became a reality through experiments—resulting in the first laser (Light Amplification by Stimulated Emission of Radiation).

• At first, lasers had no practical use and were mainly scientific demos.

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Modern Uses of Lasers (Examples of Technology in Action)

• Surgery: Laser cuts with less bleeding by cauterizing as it cuts, especially useful in eye surgery.

• Surveying and Construction: Lasers provide precise distance and alignment measurements.

• Astronomy: Lasers reflect off mirrors left on the moon to measure its distance to millimeter accuracy.

• Barcode Scanning: Lasers read the black and white bars to quickly identify items and prices.

• Laser Pointers: Even simple tools like pointers or cat toys use laser technology.

💬 Bottom Line

Technology is anything invented to solve a problem or improve life, often based on science, but not the same as science. Lasers are a powerful example of how a scientific idea became a useful technology in many parts of daily life.

Common Uses of Lasers

1. Computer Mice
   

   • Optical mice use lasers (or LEDs) to detect movement by tracking irregularities on the surface beneath them.

3. CDs, DVDs, and Blu-rays
   

   • Lasers read information encoded as tiny black marks on the disc surface.

   • A spinning disc and moving laser form a spiral path.

   • Reading lasers detect the marks, and writing (or “burning”) lasers char the plastic to create them.

   • Blu-rays use smaller blue lasers to store more data than DVDs and CDs.

5. Consumer Electronics
   

   • Found in homes, cars, and exercise gear (e.g., disc players, optical sensors).

7. Entertainment and Light Shows
   

   • Used in decorative displays like city holiday lights and Disneyland fireworks.

   • Disneyland’s “Captain EO” show used lasers for dramatic visual effects.

Laser Technology Advances

• DVDs vs. CDs: DVDs use a finer laser to increase storage.

• Blu-rays: Use blue lasers for even tighter data packing.

Science vs. Technology (broader context)

• This video also discusses the relationship between science and technology, using aspirin from willow bark as an example of technology (pain relief) preceding scientific understanding (salicylic acid discovery).

• It explains patents as a way to protect inventors’ work while still allowing science to progress.

The speaker is explaining how the concept of patenting applies to living organisms and how our manipulation of organisms over time has evolved—from natural selective breeding to modern genetic engineering, which raises new questions about what can be patented.

Here’s a summary of key points:

1. Patents protect inventions: The U.S. Patent Office ensures an invention is truly new before granting a patent. Once approved, others can use the invention but must pay royalties to the inventor.

2. Living things and patents:
   

   • You cannot patent a naturally occurring animal, plant, or bacterium because you didn’t invent them—nature did.

   • However, people react emotionally to this: they are less okay with patenting animals than bacteria.

   • But bacteria are actually vital and helpful, not just “nasty” germs.

4. Selective breeding isn’t patentable:
   

   • Over time, humans have shaped animals like cows and chickens, and crops like corn, through selective breeding—choosing and reproducing the best traits (like high milk output or large corn cobs).

   • Even though these organisms are now very different from their wild ancestors, this process is natural and gradual, so it isn’t considered inventing—and thus isn’t patentable.

6. Modern biotechnology changes this:
   

   • Now, we can directly alter the genes of organisms using science—not just slowly select traits over generations.

   • This more radical, human-driven manipulation opens the door to patenting genetically engineered organisms, because these are seen as human inventions rather than natural ones.

In short: You can’t patent what nature made, but you can patent what humans invent using modern genetic tools—even if it’s a living thing. The speaker is setting up for a discussion on genetically modified organisms (GMOs) and how they change our legal and ethical understanding of invention and nature.

What is Genetic Engineering?

Genetic engineering (or genetic manipulation) is the process of altering an organism’s DNA by adding, removing, or modifying specific genes.

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How Did We Get Here? (Historical Steps)

1. Inheritance Discovery: Scientists, including Mendel, discovered that traits are inherited from parents.

2. DNA Discovery: DNA was identified as the molecule carrying genetic information. It’s a long, spiral-shaped molecule made of genes.

3. Genes and Proteins: Genes are like “words” in a long string of letters (the DNA). Each gene is a set of instructions for building a protein, which performs specific functions in a living organism.

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How Does Genetic Engineering Work?

1. Identify a Useful Gene: Scientists find a gene with a desired trait (e.g., insect resistance).

2. Cut the Gene: Special enzymes (like molecular “scissors”) snip the gene from the DNA.

3. Insert the Gene: That gene is inserted into the DNA of another organism (like a seed), where it continues to function and produce the same protein.

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Example: Bt Corn

• Bt Bacteria: A natural soil bacterium (Bacillus thuringiensis) produces a toxin that kills insect pests when ingested.

• Genetic Engineering: Scientists at Monsanto isolated the gene responsible for this toxin and inserted it into corn seeds.

• Result: The corn (called Bt corn) makes a small amount of the insect-killing toxin in every cell.

• Benefit: Protects seeds from insect damage during storage and growing, reducing the need for chemical pesticides.

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Bt Corn

The Problem:

• Insects (especially caterpillars) chew on young corn plants, damaging crops.

• The traditional solution: pesticide sprays (tractor or plane).
  

  • These are potent nerve toxins harmful to insects and humans.

  • Can drift to nearby communities, affecting people and ecosystems.

The Solution: Bt Corn

• Scientists took a gene from the Bacillus thuringiensis (Bt) bacteria that produces an insect-killing toxin.

• They inserted this Bt gene into the DNA of corn.

• Now, every cell of the corn plant contains the toxin.
  

  • Only insects that chew on the plant are affected (and die).

  • Other insects (like pollinators) are unaffected.

• No need to spray pesticides, reducing human and environmental exposure.

Concerns:

• You’re already eating Bt corn — over half of U.S. corn is Bt.

• It’s in corn chips, corn syrup, corn flakes, corn oil, etc.

• Toxin is harmless to humans because:
  

  • It only activates in an alkaline insect gut, not our acidic stomachs.

• Short-term safety is well supported, but long-term effects are still unknown.
  

  • As the speaker says: “The experiment is underway. You’re the guinea pigs.”

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Roundup Ready Crops

The Problem:

• Weeds compete with crops for sunlight, nutrients, and water.

• Weedkillers (like Roundup) work but:
  

  • Some are persistent (stop anything from growing for years).

  • Some become flammable after use.

• Roundup (glyphosate) was better:
  

  • Kills almost any plant.

  • Breaks down in 10 days, so crops can be safely planted after.

  • But Roundup would also kill the crops if sprayed on them.

The Solution: Roundup Ready

• Scientists found some plants naturally resist Roundup.

• Isolated the gene that gives them resistance.

• Inserted that gene into crops (like soy, corn).

• Now, farmers can spray entire fields, and only weeds die — crops survive.

• Great for efficient, selective weeding with little labor.

Concern:

• After a few years, farmers noticed Roundup isn’t working as well.
  

  • Weeds have evolved resistance — it now takes more Roundup to work.

  • This is an example of evolution by natural selection in action.

  • Overuse of one solution leads to resistant “superweeds.”

    1. Weed Resistance to Herbicides: The discussion starts with farmers noticing that weeds are becoming resistant to Roundup, requiring more of the herbicide to control them. The speaker explains that weeds evolve resistance over many generations, but the rapid development of resistance suggests something unusual is happening—possibly the transfer of genetic traits from genetically modified crops (Roundup Ready crops) to the weeds.

    2. Bacterial Resistance to Antibiotics: The speaker transitions to discuss antibiotic resistance. He explains that bacteria evolve resistance quickly due to their fast generation times, unlike plants, which take longer. The overuse or misuse of antibiotics contributes to the rise of antibiotic-resistant bacteria, which are more dangerous and harder to treat.

    3. Genetic Modification in Crops: The speaker then explores genetic modification in agriculture, particularly the genetic engineering of crops to improve yields, nutritional value, and resistance to pests. The public’s resistance to genetically modified (GM) foods is noted, despite the lack of evidence showing harm from GM crops. The speaker also touches on the potential of GM crops to address malnutrition and improve food security in developing countries, particularly with examples like “Golden Rice,” which is genetically modified to combat vitamin A deficiency.

    4. Corporate Influence on GM Crops: Finally, the speaker discusses the ethical concerns surrounding GM crops, particularly the introduction of terminator genes that prevent farmers from saving seeds for future planting, forcing them to buy new seeds from corporations every year. This corporate control over food production is seen as harmful to small farmers and the long-term sustainability of agricultural practices.

    1. Medical Applications: The discussion begins with genetic modifications in animals and bacteria, particularly focusing on their medical applications, like producing insulin for diabetes treatment. Human insulin is now produced through genetically modified bacteria, which is a major breakthrough in medical biotechnology.

    2. Genetic Modification in Agriculture: The text discusses genetic modifications in crops, like Bt corn, which contains a gene that makes it resistant to pests. However, there’s a challenge of genetic modification spreading to other crops through pollination, which raises concerns about controlling genetically modified organisms (GMOs) once they are released into the environment.

    3. Ethical Concerns: Ethical concerns are raised, particularly when it comes to the patenting of genetically modified organisms. Monsanto’s legal actions against farmers using unintended GMOs is cited as an example of the ethical issues tied to corporate interests in the genetic modification of crops.

    4. Frivolous Uses: The text criticizes the frivolous application of genetic engineering, such as the creation of glow-in-the-dark potatoes and fish, questioning the usefulness and ethics of these modifications.

    5. Cloning vs. Genetic Engineering: A distinction is made between cloning and genetic engineering. Cloning, where an identical copy of an organism is made, is not considered genetic engineering because no genetic modifications are involved. Cloning does occur naturally in some organisms, but ethical concerns arise when applied to humans, especially if used for “spare parts.”

    6. Other Practices: The text clarifies that practices like feeding growth hormones or antibiotics to animals are not considered genetic engineering, even though they raise ethical concerns in terms of animal welfare and public health (e.g., antibiotic resistance).

    Overall, the text emphasizes that while genetic engineering has made significant advancements in medicine and agriculture, it requires careful consideration, especially when it comes to ethical implications and environmental impact.